KORONIS (or Coronis) was a princess of the Thessalian kingdom of Phlegyantis loved by the god Apollon. When she was pregant with his son, Koronis committed adultery with a man named Iskhys ("the Mighty"). Apollon learned of this betrayal from his raven familiar, and commanded his sister Artemis to destroy her. The goddess slew her with her deadly arrows, and struck many others down besides. But the god, feeling a pang of regret, and angered at the tattling bird, turned the raven's snow-white feathers black. He also recovered the child Asklepios from the womb of Koronis as she was burning on the pyre and entrusted him to the care of the kentauros Kheiron.

Koronis was later placed amongst the stars as the constellation Corvus ("the Crow"). In ancient Greek the crow is korônê, and the raven korax.

ENCYCLOPEDIA

CORONIS (Korônis), a daughter of Phlegyas and mother of Asclepius. (Ov. Fast. i. 291; Schol. ad Pind. Pyth. iii. 14, 48, 59.) When Coronis was with child by Apollo, she became enamoured with Ischys, an Arcadian, and Apollo informed of this by a raven, which he had set to watch her, or, according to Pindar, by his own prophetic powers, sent his sister Artemis to kill Coronis. Artemis accordingly destroyed Coronis in her own house at Lacereia in Thessaly, on the shore of lake Baebia. (Comp. Hom. Hymn. 27. 3.) According to Ovid (Met. ii. 605, &c.) and Hyginus (Poet. Astr. ii. 40), it was Apollo himself who killed Coronis and Ischys. When the body of Coronis was to be burnt, Apollo, or, according to others (Paus. ii. 26. § 5), Hermes, saved the child (Aesculapius) from the flames, and carried it to Cheiron, who instructed the boy in the art of healing and in hunting. (Pind. Pyth. iii. 1, &c.; Apollod. iii. 10. § 3; Paus. l. c.) According to other traditions Aesculapius was born at Tricca in Thessaly (Strab. xiv. p. 647), and others again related that Coronis gave birth to him during an expedition of her father Phlegyas into Peloponnesus, in the territory of Epidaurus, and that she exposed him on mount Tittheion, which was before called Myrtion.

Source: Dictionary of Greek and Roman Biography and Mythology.

Hesiod, Catalogues of Women Fragment 88 (from Strabo 9. 442) (trans. Evelyn-White) (Greek epic C8th or 7th B.C.) :
"Or like her [Koronis] who lived by the holy Twin Hills in the plain of Dotion over against Amyros rich in grapes, and washed her feet in the Boibian lake, a maid unwed."

Hesiod, Catalogues of Women Fragment 89 (from Scholiast on Pindar's Pythian Ode 3. 48) :"To him [Apollon], then, there came a messenger from the sacred feast to goodly Pytho, a crow, and he told unshorn Phoibos [Apollon] of secret deeds, that Iskhys son of Elatos had wedded Koronis the daughter of Phlegyas of birth divine."

Homeric Hymn 16 to Asclpeius (trans. Evelyn-White) (Greek epic C7th to 4th B.C.) :
"I begin to sing of Asklepios, son of Apollon and healer of sicknesses. In the Dotian plain fair Koronis, daughter of King Phlegyas, bare him, a great joy to men, a soother of cruel pangs."

Pindar, Pythian Ode 3. 5 ff (trans. Conway) (Greek lyric C5th B.C.) :
"Long ago he [Kheiron] nursed gentle Asklepios, that craftsman of new health for weary limbs and banisher of pain, the godlike healer of mortal sickness.
His mother [Koronis], daughter of Phlegyas the horseman, ere with the help of Eleithyia, the nurse of childbirth, she could bring her babe to the light of day, was in her chamber stricken by the golden shafts of Artemis, and to the hall of Death went down. For so Apollon willed. Not lightly falls the wrath of the children of Zeus. For she in the madness of her heart had spurned the god, and unknown to her father took another lover, even though her maiden bed she had already shared with Apollon of the flowing hair, and bore within her the god’s holy seed. She waited not to see the marriage feast, nor stayed to hear the sound of swelling bridal hymns, such notes as maiden friends of a like age are wont to spread in soothing songs upon the evening air. But no! her heart longed for things far off, things unknown, as many another has longed ere now . . .
Such the all-powerful, ill-fated madness that held the proud heart of fair-robed Koronis; for with a stranger, come from Arkadia, she lay in love’s embrace. Yet failed not a watching eye to see; for at Pytho, amidst the lambs of sacrifice, the temple’s king Loxias [Apollon] stood; yet saw; seeking advise from none, save that most true consultant, his all-knowing mind. For all things that are false he touches not, nor can a god, nor can a man deceive him, whether in aught they do or aught the will may purpose. Thus now, he saw that son of Eilatos, Iskhys, the stranger share her bed of love, that impious treachery; and sent his sister storming gin resistless anger to Lakereia, where by the high banks of Boibas the maiden had her home. And fate of a far other kind turned to her ruin and smote her down: and many a neighbour, too, suffered alike and was destroyed beside her; as when on the mountain from one small spark a raging fire leaps up, and lays in ruin all the widespread forest.
But when upon the high wood pure her kinsmen had set the maid, and the flames of Hephaistos shot their bright tongues around her, then cried out Apollon : `No longer shall my soul endure that my own son here with his mother in her death most pitiable should perish thus, in sorry grief.’
So spoke he and in one stride was there, and seized the babe from the dead maid; and round him the blazing flames opened a pathway. Then he took the child to the Magnetian kentauros (centaur) [Kheiron], that he teach him to be a healer for mankind of all their maladies and ills."

Isyllus, Hymn to Asclepius (trans. Frazer, Vol. Apollodorus) (Greek poet C4th or 3rd B.C.) :
"Father Zeus bestowed the hand of the Mousa Erato on Malos [eponymous lord of Malea] in holy matrimony (hosioisi gamois.) The pair had a daughter Kleophema, who married Phlegyas, a native of Epidauros; and Phlegyas had by her a daughter Aigle, otherwise known as Koronis, whom Phoibos of the golden bow beheld in the house of her grandfather Malos, and falling in love he got by her a child, Asklepios."
[N.B. This hymn was engraved on a limestone tablet unearthed at the shrine of Asklepios at Epidauros. According to the inscription the poet consulted the Delphic Oracle for approval before publishing this genealogy of the god Asklepios.]

Pseudo-Apollodorus, Bibliotheca 3. 118 (trans. Aldrich) (Greek mythographer C2nd A.D.) :
"Leukippos [king of Messenia] also was the father of Arsinoe. Apollon had sex with her, and she bore him Asklepios. Some say, however, that Asklepios was not born of Leukippos’ daughter Arsinoe, but rather of Phlegyas’ daughter Koronis in Thessalia. Apollon fell in love with her and immediately had intercourse with her, but she, despite her father’ advice, preferred Kaineus’ son Iskhys and lived with him. When a raven told Apollon this, he cursed it and turned it black in place of the white it had been before, and he killed Koronis. As she was being consumed on her funeral pyre, he snatched her baby fire and took him to the kentauros (centaur) Kheiron, who reared him and taught him medicine and hunting."

Diodorus Siculus, Library of History 4. 71. 1 (trans. Oldfather) (Greek historian C1st B.C.) :
"Asclepius was the son of Apollon and Koronis, and . . . he devoted himself to the science of healing."

Diodorus Siculus, Library of History 5. 64. 6 :
"To Apollo and Koronis was born Asklepios, who learned from his father many matters which pertain to the healing art."

Pausanias, Description of Greece 2. 26. 1 - 7 (trans. Jones) (Greek travelogue C2nd A.D.) :
"The land [of Epidauros] is especially sacred to Asklepios is due to the following reason. The Epidaurians say that Phlegyas came to the Peloponnesos, ostensibly to see the land, but really to spy out the number of the inhabitants, and whether the greater part of them was warlike. For Phlegyas was the greatest soldier of his time, and making forays in all directions he carried off the crops and lifted the cattle. When he went to the Peloponnesos, he was accompanied by his daughter [Koronis], who all along had kept hidden from her father that she was with child by Apollon. In the country of the Epidaurians she bore a son [Asklepios], and exposed him on the mountain called Titthion (Nipple) at he present day, but then named Myrtion. As they child lay exposed he was given milk by one of the goats that pastured about the mountain, and was guarded by the watch-dog of the herd. And when Aresthanas, for this was the herdsman’s name, discovered that the tale of the goats was not full, and that the watch-dog also was absent from the herd, he left, they say, no stone unturned, and on finding the child desired to take him up. As he drew near, he saw lightning that flashed from the child, and, thinking that it was something divine, as in fact it was, he turned away.
Presently it was reported over every land and sea that Asklepios was discovering everything he wished to heal the sick, and the he was raising dead men to life.
There is also another tradition concerning him. Koronis, they say, when with child with Asklepios, had intercourse with Iskhys, son of Elatos. She was killed by Artemis to punish her for the insult done to Apollon, but when the pure was already lighted Hermes is said to have snatched the child from the flames.
The third account is, in my opinion, the farthest from the truth; it makes Asklepios to be the son of Arsinoe, the daughter of Leukippos. For when Apollophanes, the Arkadian, came to Delphoi and asked the god if Asklepios was the son of Arsinoe and therefore a Messenian, the Pythian priestess gave this response:--`O Asklepios, born to bestow great joy upon mortals, pledge of the mutual love I enjoyed with Phlegyas’’ daughter, lovely Koronis, who bare thee in rugged land, Epidauros.’
The oracle makes it quite certain the Asklepios was not a son of Arsinoe, and that the story was a fiction invented by Hesiod, or by one of Hesiod’s interpolators, just to please the Messenians."

Pausanias, Description of Greece 2. 11. 7 - 12. 1 :"[In the sanctuary of Asklepios at Titane in Sikyonia :] There is also a wooden image of Koronis, but it has no fixed position anywhere in the temple. While to the god are being sacrificed a bull, a lamb, and a pig, they remove Koronis to the sanctuary of Athena and honor her there. The parts of the victims which they offer as a burnt sacrifice, and they are not content with cutting out the thighs, they burn on the ground, except the birds, which they burn on the altar . . . In Titane there is also a sanctuary of Athena, into which they bring up the image of Koronis."
[N.B. Pausanias does not say what type of bird was sacrificed to Asklepios. The removal of the statue of Koronis might suggest ravens or crows. Although the usual bird offering to the god was the rooster, cf. Plato.]

Pausanias, Description of Greece 4. 3. 2 :
"They say that the sons of Asklepios who went to Troy were Messenians, Asklepios being the son of Arsinoe, daughter of Leukippos, not the son of Koronis, and they call a desolate spot in Messenia by the name of Trikka."

Pseudo-Hyginus, Fabulae 202 (trans. Grant) (Roman mythographer C2nd A.D.) :
"When Apollo had made Coronis, daughter of Phlegyas, pregnant, he put a crow in guard, so that no one should violate her. But Ischys, son of Elatus, lay with her, and becuase of this he was killed by the thunderbolt of Zeus. Apollo struck the pregnant Coronis, and killed her. He took Ascelpius from her womb and reared him, but the crow who had guarded her he turned from white to black."

Pseudo-Hyginus, Fabulae 14 :
"Asclepius, son of Apollo and Coronis, from Tricca."

Pseudo-Hyginus, Astronomica 2. 40 :
"Istrus [Greek historian C3rd B.C.] and several others have said that the Crow [i.e. the constellation Corvus] was Coronis, daughter of Phlegyas. She bore Aesculapius to Apollo, but after Ischys, son of Elatus, had lain with her, the crow, which had noted it, reported it to Apollo. For his unpleasant news Apollo changed him to black instead of his former white color, and transfixed Ischys with his arrows."

Ovid, Metamorphoses 2. 536 & 596 ff (trans. Brookes More) (Roman epic C1st B.C. to C1st A.D.) :
"Long ago the ravens were not black--their plumage then was white as any dove--white-feathered, snow-white as the geese . . . as white as swans that haunt the streams. Disgrace reversed the raven's hue from white to black, because offense was given by his chattering tongue. O glorious Phoebus [Apollon]! dutiful to thee, Coronis of Larissa, fairest maid of all Aemonia, was a grateful charm, a joy to thee whilst faithful to thy love,--while none defamed her chastity. But when the Raven, bird of Phoebus, learned the Nymph had been unfaithful, mischief-bent that bird, spreading his white wings, hastened to impart the sad news to his master. After him the prattling Crow followed with flapping wings, eager to learn what caused the Raven's haste . . .
Now replied the Raven to the Crow, that talked so much, `A mischief fall upon your prating head for this detention of my flight. Your words and warnings I despise.' With which retort he winged upon his journey, swiftly thence in haste, despite the warning to inform his patron, Phoebus, how he saw the fair Coronis with a lad of Thessaly.
And when Apollo, Phoebus, heard the tale the busy Raven made such haste to tell, he dropped his plectrum and his laurel wreath, and his bright countenance went white with rage. He seized his trusted arms, and having bent his certain bow, pierced with a deadly shaft that bosom which so often he had pressed against his own. Coronis moaned in pain,--and as she drew the keen shaft from the wound, her snow-white limbs were bathed in purple blood: and thus she wailed, `Ah, Phoebus! punishment is justly mine! but wherefore didst thou not await the hour of birth? for by my death an innocent is slain.' This said, her soul expired with her life-blood, and death congealed her drooping form.
Sadly the love-lore God repents his jealous deed; regrets too late his ready credence to the Raven's tale. Mourning his thoughtless deed, blaming himself, he vents his rage upon the talking bird; he hates his bow, the string, his own right hand, the fateful arrow. As a last resource, and thus to overcome her destiny, he strove to cherish her beloved form; for vain were all his medicinal arts. But when he saw upraised the funeral pyre, where wreathed in flames her body should be burnt, the sorrow of his heart welled forth in sighs; but tearless orbed, for no celestial face may tide of woe bedew. So grieves the poor dam, when, swinging from his right the flashing ax, the butcher with a sounding blow divides the hollow temples of her sucking calf. Yet, after Phoebus poured the fragrant myrrh, sweet perfumes on her breast, that now once more against his own he pressed, and after all the prematurely hastened rites were done, he would not suffer the offspring of his loins to mingle with her ashes, but he plucked from out the flames, forth from the mother's thighs his child, unborn, and carried to the cave of double-natured Chiron. Then to him he called the silly raven, high in hopes of large requital due for all his words; but, angry with his meddling ways, the God turned the white feathers of that bird to black and then forbade forever more to perch among the favoured birds whose plumes are white."